Or you rely on media and, in countries where that's available, stuff like the government-backed, independent "Stiftung Warentest" in Germany ("foundation for testing products").
Want really good and consistent quality vegetable tanned leather made in Poland? Then she said that there is basically one place (they produce it from over 110 years, and they are quite low in Google searches). Want chrome tanned leather with a lot of colors that are consistent and ALWAYS the same as on sampler? Also only one place.
I was later learning normal sewing with her mother. When asked about good quality cotton (or other natural) materials in small quantities she basically say: "well, it will be quite hard and when I want really good materials I order them straight from Italy, available only in wholesale quantities from few manufacturers that I veted over last 40 years". She later said that in textile industry you can't really trust anybody, because they can send you few batches of great quality and then suddenly lower quality and will be telling straight to your face that "quality was always like that"...
Often those products do exist, but you need to become an “expert in X” to find them.
Oh… you want to buy a high quality leather [whatever], better start learning about leather grades, leather tanneries, stitching thread, stitching types… so it doesn’t blow out in a year.
Except we can’t all become experts in all products, and many companies are perfectly happy to build a brand on quality and then slowly erode that quality to increase margins.